Henwen, meaning "Old White", is in Welsh legend a sow (female pig) which according to the Welsh Triads gave birth to Cath Palug, a monstrous cat depicted as combating with either Cai (Sir Kay) or King Arthur of Arthurian Legends. According to the triad "Three Powerful Swinherds of the Isle of Britain", the sow was kept by one Coll, son of Collfrewy, a pigkeeper for Dallwyr Dallben (also spelt Dallweir).